For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
I tried that. After turning off pp2v5_nand0 the other [20v capable] non-working board still got to 20v.
So I suspect this would indicate that reading a NAND partition is not required before going to 20v.
Can any other area explain pp3v8_aon oscillating 2.5v to 3.4 avg 3.2v?
I do happen to have another non-working board - measurements from this in brackets at end of line
pp5v_s2. 0.3v close to OBdata 0.39v
pp1v2_s2 0.2v close to OBdata 0.26v
pp1v8_s2 0.22v close to OBdata 0.255v
pp1v8_aon 0.4v close to OBdata 0.44...
Lady's a2485 just stopped.
No visible liquid damage to board
5volts 20mA not connected to battery, trackpad
ppbus_aon 12.3v
pp3v8_aon oscillating 2.5v to 3.4 avg 3.2v (low)
I noticed U5700 has an erratic input voltage pp5v_s2_main 0.6v to 5v
p5vs2tps_pwr_en 0.2v but Im going around in circles...
Macbook boots just fine with a new battery and will charge it.
But when left for a day or two off charge and shutdown it flattens the battery and then won't boot.
CmiZapper Battery Tool reports a drain of 90mA even when shutdown as cells drop below 3v each. This looks large to me when a...
Fans well clogged
No visible evidence of liquid damage
20v 2a, battery is being charged
no boot chime
fans spin
caps lock light toggles
no internal LCD image or backlight
no external video, also tried when internal LCD disconnected
Tried good screen, still nothing.
L8504 not blown
Was able to...
The voltage levels for the NANDS appear good. Doesn't a bad NAND normally develop a short that would pull these down?
pp0v9_nand0 0.9v
pp1v2_nand0 1.2v
pp2v5_nand0 2.5v
ppvin_p3v8nand0 3.8v
I noticed ppvdd_ldo_nand0_ocarina is only 1.4v rather than schematics 2.5v
Before the CD3217 negotiate...
I understand you are saying 3V3_S2 comes from the U8100 and there may be problems with that chip and that chip has a healthy power supply in PP3V8_AON_VDDMAIN.
But is it being told to turn on? In FlexBV notes there is a list of things that come before "step 11 (Many rails appear now)". Is that...
But the asymmetry described in my post #6 is not present on the working board. The rom gets 3.3v no matter which channel is powered.
Anyway do you suggest I replace U8100?
Ive just taken delivery of a locked identical board that gets to 20v. Ive just taken its CD3217s and I still get that asymmetry described in my post #6.
So the rom only gets 3.3volts when charger on channel0 and 0.5v when on channel1.
There are no voltages on inductors around U8100.
OK the original CD3217 back in their places.
ppbus_aon 12.3v
3v8_aon 3.8v
When charger connected to channel 0
pp3v3_upc0_ldo [which powers the ROM] only gets 3.3 volt when
pp3v3_upc1_ldo sits at 0.4v
when charger connected to channel 1
pp3v3_upc0_ldo [which powers the ROM] gets 0.4 volts...
Pressing power button when on charger [or on battery] would result in Apple logo for 2 seconds before shutoff.
Original battery was not charging. Battery replaced, battery now charges. Given a good charge.
Still only reaches Apple logo before shutoff.
Corrosion on CF800, CF813 but DM voltages...
The point I am making is that ROM chip is only getting the correct voltage on one channel. Something seems wrong and Im wondering if this is what stopping it shift to 20v. Ive replaced both CD3217 with new and now Im wondering if I have overtemped one.
ppbus_aon 12.3v
3v8_aon 3.8v
When charger connected to top USBC port [nearest screen]
pp3v3_upc0_ldo [which powers the ROM] only gets 3.3 volt when
pp3v3_upc1_ldo sits at 0.4v
when charger connected to lower USBC port
pp3v3_upc0_ldo [which powers the ROM] gets 0.4 volts
pp3v3_upc1_ldo sits...
Tried DFU revive with trackpad, battery and touchid connected. Still seeing apple logo and progress bar.
But I am getting another error message and didn't spot when it changed from 1.
AMRestoreErrorDomain 1101
Failed to handle message type
ASR invertor error
I'm seeing heat of 70c on the...